Add validation caching interface.

src/trusted/service_runtime/sel_validate_image.c

 /*
  * Copyright (c) 2012 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "native_client/src/shared/platform/nacl_log.h"
 #include "native_client/src/trusted/service_runtime/sel_ldr.h"
 #include "native_client/src/trusted/validator/ncvalidate.h"
 
@@ skipping 11 matching lines @@
     case NaClValidationFailedSegmentationIssue:
     default:
       return LOAD_VALIDATION_FAILED;
   }
 }
 
 int NaClValidateCode(struct NaClApp *nap, uintptr_t guest_addr,
                      uint8_t *data, size_t size) {
   NaClValidationStatus status = NaClValidationSucceeded;
   enum NaClSBKind sb_kind = NACL_SB_DEFAULT;
+
+  NaClValidationCache *cache = nap->validation_cache;
+
   if (nap->validator_stub_out_mode) {
+    /* Validation caching is currently incompatible with stubout. */

[Mark Seaborn, 2012/03/01 00:26:20]

Technically, the second pass is not incompatible.

[Nick Bray (chromium), 2012/03/01 01:25:16]

Based on future plans, validating code twice without knowing if the first pass
modified it is a potential security hole.

+    cache = NULL;
     /* In stub out mode, we do two passes.  The second pass acts as a
        sanity check that bad instructions were indeed overwritten with
        allowable HLTs. */
     status = NACL_SUBARCH_NAME(ApplyValidator,
                                NACL_TARGET_ARCH,
                                NACL_TARGET_SUBARCH)(
                                    sb_kind,
                                    NaClApplyValidationDoStubout,
                                    guest_addr, data, size,
-                                   nap->bundle_size, &nap->cpu_features);
+                                   nap->bundle_size, &nap->cpu_features,
+                                   cache);
   }
   if (status == NaClValidationSucceeded) {
     status = NACL_SUBARCH_NAME(ApplyValidator,
                                NACL_TARGET_ARCH,
                                NACL_TARGET_SUBARCH)(
                                    sb_kind,
                                    NaClApplyCodeValidation,
                                    guest_addr, data, size,
-                                   nap->bundle_size, &nap->cpu_features);
+                                   nap->bundle_size, &nap->cpu_features,
+                                   cache);
   }
   return NaClValidateStatus(status);
 }
 
 int NaClValidateCodeReplacement(struct NaClApp *nap, uintptr_t guest_addr,
                                 uint8_t *data_old, uint8_t *data_new,
                                 size_t size) {
   enum NaClSBKind sb_kind = NACL_SB_DEFAULT;
   if (nap->validator_stub_out_mode) return LOAD_BAD_FILE;
 
@@ skipping 50 matching lines @@
         NaClLog(LOG_ERROR,
                 "Run sel_ldr in debug mode to ignore validation failure.\n");
         NaClLog(LOG_ERROR,
                 "Run ncval <module-name> for validation error details.\n");
         rcode = LOAD_VALIDATION_FAILED;
       }
     }
   }
   return rcode;
 }